Mississippi Cosmetology Board Practice Exam

The correct answer describes hair as a filamentous protein structure, which accurately reflects the primary composition and structure of hair. Hair is primarily made up of a protein called keratin. Keratin is a fibrous structural protein that provides both strength and resilience, making it essential for hair's durability. This filamentous nature refers to the elongated, thread-like form of protein that contributes to the tensile strength and flexibility of hair strands.

In contrast, other options refer to structures that do not accurately represent hair. A lipid membrane structure would suggest a composition based on fats and oils, which is not the characteristic of hair. Hair might be influenced by lipids in terms of moisture and shine, but it does not have a lipid-based structure. A carbohydrate-based structure implies a composition primarily made of sugars or starches, which again does not account for the protein-based nature of hair. Lastly, a nucleic acid structure pertains to DNA and RNA, essential for genetic instructions but not relevant to the physical composition of hair itself. This understanding highlights the significance of protein in maintaining healthy hair and informs various hair care practices.